1. Field of the Invention
The present invention relates to a mounting structure for a non-polar inorganic ceramic capacitor having a steatite, titanium, barium titanate, strontium or similar ceramic as a dielectric material on to which electrodes are directly printed.
2. Description of the Related Art
Examples of conventional ceramic capacitors of this sort include the flat type illustrated in FIG. 1, and the block type illustrated in FIG. 2. Flat-type ceramic capacitor comprises a flat capacitor element 1 and flat electrodes 2a and 3a attached to the upper and lower surfaces thereof. The object of the electrodes 2a and 3a is both to cool the capacitor element 1 and to provide conductivity.
Block-type ceramic capacitor comprises a block-shaped capacitor element 4, and L-shaped electrodes 5, 6 which are attached to the bottom of the capacitor element 4 and connected electrically thereto. The object of the L-shaped electrodes 5, 6 is simply to provide conductivity.
Conventional ceramic capacitors as described above are characterized by high dielectric constant (permittivity), and can thus be rendered compact, while the fact that the capacitor element is inorganic brings the added advantage of relative absence of functional deterioration.
However, it is a common requirement according to application, as for instance in a power converter, that it be possible to lower the impedance in the wiring route connecting the ceramic capacitor and other electronic components.
Accordingly, one object of the present invention is to provide a novel ceramic capacitor mounting structure wherein it is possible to lower the impedance in the wiring routes connecting the ceramic capacitor and other electronic components, while at the same achieving an excellent cooling effect.
With a view to attaining the aforesaid object, the present invention is a ceramic capacitor mounting structure comprising a flat capacitor element, and first and second electrodes connected to an opposite surface of the capacitor element respectively, and having extension member which extend outward from the periphery of the capacitor element respectively; and first and second connectors attachable to the extension member of the first and second electrodes respectively. By virtue of the present invention, impedance in the wiring route between the capacitor element and the bus bars is reduced, while the extensions to the electrodes act as a radiation fin, thus improving the cooling effect.
With a view to attaining the aforesaid object, the present invention is a ceramic capacitor mounting structure comprising
a ceramic capacitor comprising:
a flat capacitor element;
a first and second electrodes connected respectively to opposite surfaces of the capacitor element; wherein the ceramic capacitor is located between direct-current terminals of an inveter designed to permit a two-level alternating-current output; and
the direct-current terminals and the first and second electrodes being connected electrically and mechanically.
The fact that by virtue of the present invention the direct-current terminals and the electrodes of the capacitor are directly connected in this manner contributes to achieving lower impedance.
With a view to attaining the aforesaid object, the present invention is a ceramic capacitor mounting structure comprising
a ceramic capacitor comprising:
a flat capacitor element;
a first and second electrodes connected respectively to opposite surfaces of the capacitor element; wherein two ceramic capacitors are respectively located between a neutral terminal and direct-current terminals of an inverter to permit a three-level alternating-current output; and
the neutral terminal and the first and second electrodes being each connected electrically and mechanically.
The fact that by virtue of the present invention the direct-current terminal and the neutral terminal are directly connected in this manner to the electrodes of the first capacitor, while the neutral terminal and the direct-current terminal are directly connected to the electrodes of the second capacitor contributes to achieving lower impedance.
With a view to attaining the aforesaid object, the present invention is a ceramic capacitor mounting structure comprising a flat capacitor element; a single electrode connected electrically to one surface of the capacitor element; an electrode body connected electrically to the other surface of the capacitor element; and a coolant passage structuring member fashioned integrally with the electrode body and carrying a coolant to facilitate the cooling of the electrode body.
By virtue of the present invention the upper electrode is cooled in this manner, as is the capacitor element, a configuration which contributes to rendering the structure more compact.
With a view to attaining the aforesaid object, the present invention is a ceramic capacitor mounting structure comprising a flat capacitor element; a single electrode connected electrically to one surface of the capacitor element; an electrode body connected electrically to the other surface of the capacitor element; and a cooling fin fashioned integrally with the electrode body and serving to increase the radiation effect.
By virtue of the present invention the upper electrode is cooled in this manner by the cooling fin, as is the capacitor element, a configuration which contributes to rendering the structure more compact.
With a view to attaining the aforesaid object, the present invention is a ceramic capacitor mounting structure comprising a plurality of ceramic capacitors comprising a flat capacitor element and two electrodes each connected electrically to opposite surfaces of the capacitor element, wherein the ceramic capacitors are located between two flexible bus bars, and the electrodes are connected electrically and mechanically to the flexible bus bars respectively.
The fact that by virtue of the present invention a plurality of ceramic capacitors is connected parallelly in this manner with the aid of the flexible bus bars contributes to achieving lower impedance because it allows the wiring route to be shortened in comparison with a conventionally-wired parallel connection.
With a view to attaining the aforesaid object, the present invention is a ceramic capacitor mounting structure comprising a single ceramic capacitor which comprises a flat capacitor element and a electrode connected electrically to one surface of the capacitor element;
a single semiconductor power element which comprises a semiconductor power element chip mounted on and connected electrically to a substrate with a pattern wiring;
wherein the ceramic capacitor and the semiconductor power element are connected electrically in parallel, and
a wiring for use in external connection being located between the other surface of the capacitor element and the other surface of the chip, the capacitor element and the chip being connected electrically and mechanically.
By virtue of the present invention this configuration contributes to achieving lower impedance because it allows the wiring route between the capacitor element and the semiconductor power element chip to be shortened.
With a view to attaining the aforesaid object, the present invention is a ceramic capacitor mounting structure wherein a snubber circuit comprising a serially connected diode and capacitor is connected electrically to a single semiconductor power element in parallel fashion; the ceramic capacitor comprising a flat capacitor element and a single electrode connected electrically to one surface of the capacitor element; the diode comprising a substrate with a wiring pattern, and diode chip mounted on and electrically connected to the substrate; and the surface of the capacitor element to which no electrode is connected, and the wiring pattern on the surface of the substrate on which no diode chip is mounted are connected electrically.
The fact that by virtue of the present invention the capacitor element and DBC (that is to say, Direct Bonding Copper) substrate with the diode chip mounted thereon are directly connected electrically and mechanically in this manner contributes to achieving lower impedance because it allows the wiring route between the serial circuit comprising the capacitor element and diode chip on the one hand and the power element chip on the other hand to be shortened.
With a view to attaining the aforesaid object, the present invention is a ceramic capacitor mounting structure comprising a semiconductor power element which comprises a semiconductor power element chip which mounted on a substrate with a wiring pattern, has electrically connected thereto for use in external connection an emitter and a collector terminal;
a ceramic capacitor which comprises a flat capacitor element;
a diode comprising a substrate with a wiring pattern and diode chip mounted on and electrically connected to the substrate;
wherein the semiconductor power element, the ceramic capacitor and the diode are serially connected; and
one surface of the capacitor element is connected electrically to a surface of an emitter terminal of the semiconductor power element, and the other surface of the capacitor element and the wiring pattern of the substrate on which the diode chip is mounted are connected electrically.
The fact that by virtue of the present invention the semiconductor power element chip with the emitter is connected directly to the capacitor element in this manner, as is also the wiring pattern of the DBC substrate with the diode chip mounted thereon, contributes to achieving lower impedance. A power converter configured after this fashion is very effective in lowering impedance.
With a view to attaining the aforesaid object, the present invention is a ceramic capacitor mounting structure comprising a single semiconductor power element; a plurality of ceramic capacitors; and first and second substrates with wiring patterns; wherein the semiconductor power element is located between the first and second substrates, and has a chip housed within a circular package, and emitter, collector and gate terminals which are connected electrically to the chip and led outside the package, while also being connected electrically to the wiring patterns on the first and second substrates; and the ceramic capacitor is located between the first and second substrates on the periphery of the circular package of the semiconductor power element, the circular capacitor element being divided radially, while the divided capacitor elements are connected electrically to the wiring patterns on the first and second substrates.
By virtue of the present invention this sort of configuration makes it possible to achieve lower impedance and greater compactness.
With a view to attaining the aforesaid object, the present invention is a ceramic capacitor mounting structure wherein a snubber circuit comprising a serially connected ceramic capacitor and diode is connected electrically in parallel fashion to a single semiconductor power element; the ceramic capacitor comprising a flat capacitor element and an electrode, which forms one surface of this capacitor element whereto it is connected electrically; the diode having a diode chip, in addition to a cathode and an anode which are connected electrically to the diode chip and further act as cooling fins; and either the cathode terminal or the anode terminal of the diode is connected electrically and mechanically to the opposite surface of the capacitor element from the electrode to constitute a moulded layer wherein the periphery of the diode chip is embedded in such a manner that the cathode and anode terminals are exposed.
The fact that by virtue of the present invention the periphery of the diode chip is embedded in the moulded layer in this manner contributes to improving insulation performance around the chip, and helps to render the structure more compact.
With a view to attaining the aforesaid object, the present invention is a ceramic capacitor mounting structure comprising a semiconductor power element chip constituting a power converter, or a snubber diode chip, or both these; and a ceramic capacitor, wherein the ceramic capacitor comprises a flat capacitor element, first and second electrodes connected electrically and mechanically to opposite surfaces of the capacitor element, and first and second plugs respectively connected electrically and mechanically to the electrodes; and the semiconductor power element or snubber diode is equipped with a package, a chip housed within this package, and terminals comprising an emitter, collector and gate, or a cathode and an anode, while receptacles provided within the package and connected electrically to the terminals are capable of being connected to and released from the plugs in the ceramic capacitor.
The fact that by virtue of the present invention the capacitor element and either the semiconductor power element chip, the snubber diode chip, or both are connected in this manner by way of the plugs and the receptacles makes it possible to achieve lower impedance and greater compactness.
With a view to attaining the aforesaid object, the present invention is a ceramic capacitor mounting structure wherein a single ceramic capacitor is connected between first and second direct-current terminals in an inverter designed to permit a two-level alternating-current output; the ceramic capacitor comprising a block-shaped capacitor element and L-shaped first and second electrodes each connected electrically to one surface of the capacitor element; and an insulating body is located between the direct-current terminals, while apertures are formed which penetrate the insulating body and the direct-current terminals, an insulating layer being formed around the aperture in the first direct-current terminal, and a conductive pin being inserted through the aperture formed in the insulating layer, the aperture in the insulating body and the aperture in the second direct-current terminal, serving respectively to fix the second electrode of the capacitor electrically to the second direct-current terminal, and to fix the first electrode of the capacitor electrically directly to the first direct-current terminal.
The fact that by virtue of the present invention the electrode is connected directly to the first direct-current terminal, while the electrode is connected electrically to the second direct-current terminal immediately below this contributes to lowering impedance.
With a view to attaining the aforesaid object, the present invention is a ceramic capacitor mounting structure wherein two ceramic capacitors are connected between first and second direct-current terminals and a neutral terminal in an inverter designed to permit a three-level alternating-current output; the first and second ceramic capacitors comprising block-shaped capacitor elements and L-shaped first and second electrodes each connected electrically to one surface of the capacitor elements; and first and second insulating bodies are located respectively between the first direct-current terminal and the neutral terminal, and between the second direct-current terminal and the neutral terminal, while apertures are formed which penetrate respectively the first and second insulating bodies, the first and second direct-current terminals, and the neutral terminal, insulating layers being formed around the apertures in the first and second direct-current terminals respectively, and conductive pins being inserted respectively through the apertures formed in the insulating layers, the apertures in the first and second insulating bodies, and the aperture in the neutral terminal, serving respectively to fix the second electrodes of the first and second ceramic capacitors electrically to the neutral terminal, and to fix the first electrodes of the first and second ceramic capacitors electrically directly to the direct-current terminals.
The fact that by virtue of the present invention the electrode of the first ceramic capacitor is connected directly in this manner to the direct-current terminal, the second electrode of the first ceramic capacitor being connected electrically to the neutral terminal immediately below this, while the electrode of the second ceramic capacitor is connected directly to the direct-current terminal, the second electrode of the second ceramic capacitor being connected electrically to the neutral terminal immediately below this contributes to lowering impedance.